The following five United States patents relate to the art of making electrical connections between electric lines in adjacent railway cars.
U.S. Pat. No. 3,251,480, issued to K. L. DePenti et al on May 17, 1966. This patent provides a connector for automatic connection of fluid pressure conduits and electrical circuits. The connector is located underneath the coupler and joining of the connectors is intended to occur automatically as the cars are coupled. This system is inconsistent with the industry standard brake line fluid pressure connector. No redundancy of contacts is provided, nor wiping action.
U.S. Pat. No. 3,646,498, issued to R. T. Reed et al on Feb. 29, 1972. This is an electrical connector which is not associated with a fluid pressure connector. Electrical contacts are embedded in insulating blocks, and are brought into electrical contact by pins activated when the connectors are joined. No redundancy of contacts is provided, nor wiping action.
U.S. Pat. No. 3,773,186, issued to W. H. Reno et al on Nov. 20, 1973. This patent has contacts in bores, which are placed in electrical contact by fluid pressure. No redundancy of contacts is provided, nor wiping action.
U.S. Pat. No. 3,812,444, issued to W. H. Reno on May 21, 1974. This is a combined fluid pressure connector and electrical connector which is inconsistent with the industry standard brake line fluid pressure connector. No redundancy of contacts is provided, nor wiping action.
U.S. Pat. No. 5,586,668, issued to Craig Miller on Dec. 24, 1996. This patent describes a fluid pressure connector for joining brake airlines in coupled railway vehicles. The invention includes electrical contacts which join electrical communication lines in the two railway vehicles. This invention can be connected to the industry standard brake line fluid pressure connector for fluid pressure connection only. In this manner, a railway vehicle equipped with the new connector can be joined to a railway vehicle equipped with the old connector and still retain the required brake line fluid pressure connection. This invention implicitly presupposes that if electronic systems on a railway vehicle joined by this connector are to be connected to the electrical communication lines which are connected between railway vehicles, a junction box would be mounted on the railway vehicle and the cables to the electronic apparatus and the electrical communication lines which are connected between railway vehicles are joined in the junction box.
The applications which are cited above describe various proposed alternative configurations for combined fluid pressure connectors and electrical communication line connectors. The application having Ser. No. 08/688,436 describes a shutoff valve for closing the brake line which is used when a railway vehicle is disconnected from an adjacent vehicle. In practice, as when two cars are deliberately uncoupled, at least one of the valves on one of the adjacent ends of the two coupled cars is closed before the cars are pulled apart, which is when the airlines pull apart and are thereby disconnected.
In the application just cited, the moveable portion of the valve is connected to a moveable portion of an electrical switch so that when the valve is closed, prior to separating two railway vehicles, the switch is opened so that when the connectors pull apart, no voltages will be present on the exposed contacts of the electrical portions of the connectors.
None of the applications cited above provide means for connection of electrical or electronic systems on a railway vehicle to electrical trainline cables connected between railway vehicles. Generally, to provide connection of electrical or electronic systems, a special junction box is provided which is mounted on the railway vehicle and to which the trainline cables are attached and to which a branching electrical cable is attached which in turn is attached to the electrical or electronic systems.
If a railway vehicle is not equipped with such a junction box, then in order to retrofit it with an electrical or electronic system, it is necessary to install a junction box.